<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>使用XHR封装ajax请求参数</title>
</head>
<body>
  <button onclick="testGet()">发送GET请求</button><br>
  <button onclick="testPost()">发送POST请求</button><br>
  <button onclick="testPut()">发送PUT请求</button><br>
  <button onclick="testDelete()">发送Delete请求</button><br>
</body>
</html>